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|    sci.math.symbolic    |    Symbolic algebra discussion    |    10,432 messages    |
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|    Message 9,633 of 10,432    |
|    Albert Rich to clicl...@freenet.de    |
|    Re: can your system handle 4th-root pseu    |
|    22 Sep 17 13:37:01    |
      From: Albert_Rich@msn.com              On Friday, September 22, 2017 at 6:58:04 AM UTC-10, clicl...@freenet.de wrote:       > Albert Rich schrieb:       > >        > > As Martin pointed out, when m=0 and n=1 or when m=2 and n=3 these       > > integrals are pseudo-elliptic. However for other even values of m,       > > the optimal antiderivatives do seem to require a single, simple       > > elliptic term. Do you concur?       >        > I suppose this is most easily answered by means of a capable algebraic       > Risch integrator.              For the antiderivative of x^2/((2-x^2)*(x^2-1)^(1/4)) Rubi 4.13.3 gets               ArcTan[x/(Sqrt[2]*(x^2-1)^(1/4))]/Sqrt[2] +         ArcTanh[x/(Sqrt[2]*(x^2-1)^(1/4))]/Sqrt[2] -         2*(1-x^2)^(1/4)/(x^2-1)^(1/4)*EllipticE[ArcSin[x]/2,2]              involving only a single EllipticE function. If this was actually a       pseudo-elliptic integral, that would imply EllipticE[ArcSin[x]/2,2] could be       expressed in terms of elementary functions. But surely that is not the       case(?). Ergo the integral is        elliptic.              Albert               --- SoupGate-Win32 v1.05        * Origin: you cannot sedate... all the things you hate (1:229/2)    |
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